Have you thought about experimenting with planting some avocado pits. I planted a bunch in pots and will be putting them out in the spring.

Compare your climate to Escondido California, a large avo growing area.

this may help you decide if it is possible. Mostly hass grown there.

Are you committed to growing it in a container? There are other varieties that, at least according to what I've read, are considerably hardier than Stewart, and would likely do fine in the ground. I'm in NW Tucson and my in-ground Wilma (genetically the same as Brazos Belle) and Opal (genetically the same as Lila) are both doing well; the Wilma grows like a weed and produced a lot of fruit last year. A neighbor recently cut down a couple of 30-year-old Zutanos, which kept him well-supplied with avocados until the trees finally got diseased. I know someone else on the NW side with a couple of unprotected Mexicola Grandes which are thriving and producing, and I'm aware of two other large trees in Tucson. I recently planted an Aravaipa and a Mexicola Grande in my yard but they're still too young to extrapolate from; I also plan to try a few others and will start grafting them as soon as my rootstocks are big enough.

Here's the Wilma (planted in spring of 2013) just before a recent heavy pruning; the Opal is the little guy in the left foreground:

Some of last year's Wilma crop:

Good information. Thank you. I'm not committed to container growing, but just trying to simplify a few things (this too shall pass). I'm familiar with Zutano, but how is the fruit quality with the other varieties you mentioned?

I haven't tasted Aravaipa, and have heard both positive and negative assessments--but none of the opinions were from anyone who had actually eaten the fruit. I haven't tasted Mexicola Grande either, but the owner of the trees I mentioned says his wife claims they're the best avocados she's eaten. My Opal is still quite small, but it produced its first solitary fruit last year. It got knocked off the tree by a critter before being fully mature, but still tasted good. I have eaten many fruit from my Wilma, and I think the flavor & texture are excellent; quite a few of my friends and family have tried it as well, and they concur. However, it's different from Hass and other grocery store varieties that most people are familiar with. It has a thin, black, edible skin (as delicate as on a tomato), and would be very difficult to peel--so if you are put off by black bits in your guacamole, it's not the variety for you.

It also has a loose seed, and the seedcoat adheres lightly to the flesh, so it usually has to be picked out of the seed cavity. It's easy to do, but fussier than what you'll be used to.

In my mind, the main advantages are, 1) It can thrive in Tucson--mature trees are purportedly hardy to 16 degrees, and mine also seems unfazed by the heat or soil (however, my soil is pretty good), 2) It grows fast and bears heavily, at a young age (mine was planted in 2013; it produced its first 14 avocados in 2015, and around 75 in 2016).

Here are some other cold hardy avocado varieties you might consider.

I have the following cold hearty trees in containers: Bacon, Fuerte, Hass, Mexicola, Stewart, Wurtz. I also have less cold hearty ones in containers such as Pinkerton and Holiday. All are doing well and we got down to 28* this winter. I only covered the pinkerton and holiday during the cold weather and they are all doing well.

Nick--how old/large are your trees, and where are you located? Are any of them fruiting yet? Do you plan to maintain them in containers indefinitely, or do you intend to eventually plant them in the ground?

They are going on their 2 to 3rd years . I'll have fruit this year on 6 of the 8. One of my previous fruiting trees will not fruit this year due to transplanting into a larger container. All my trees will stay in containers. I don't want any of them to be over 8 foot

Please keep us updated on the fruit quality of your various cultivars, and anything else you think might be useful. Where are you located?

They look great--congratulations! How hot does it get in your yard during the summer? Do you have to provide any protection for the trees?

No protection 100 plus and consistently in the mid to upper 90's

Thanks to all for the excellent answers and observations. My apologies for not responding sooner, but "life stuff" popped up as it has a habit of doing. My original intent with container growing was to limit growth, but all the feedback has given me no end of ideas. As to the Wilma variety, if it does leave some black bits in my guacamole, I'll just leave the cilantro a little more coarsely chopped. Problem solved! I'm not at all put off my non-grocery store varieties. Part of my first job out of college was taking care of an experimental avocado orchard in the Santa Barbara, CA area. It contained several varieties that had outstanding flavor, but couldn't cut it on the commercial market because they didn't "look" like avocados. Thanks again to you all for the great information.

I don't know if it's possible to send a PM on this forum, but if you're interested in seeing my trees you're welcome to contact me (Ken Stockton) through a couple of facebook groups--Phoenix Fruit Growers and Tucson Fruit Growers.

Nick thank you so much for sharing about your trees fruiting in containers! I am from the same school of thought, in that I don't really want my trees to get over 8 feet and my climate is similar to yours. I am trying avocados in containers and my idea has been poo-pooed by others, saying it won't work and they won't fruit. It's really nice to see that it does work. Great job!!!